GridView Clear Input Before Commit in Deferred Search Mode

Updated on Sep 24, 2025

Environment

Product Version	2022.3.912
Product	RadGridView for WPF

Description

When the IsSearchingDeferred property of RadGridView is set to True, the clear button will remove the search input only if it is committed.

This article will show you how to clear the search value every time the clear button is clicked.

Solution

1. Subscribe to the Loaded event of RadGridView and retrieve the search-as-you-type TextBox element and cache it. Then, retrieve the RadButton control used for clearing the input. This can be done using the ChildrenOfType extension method.

   Retrieve the search-as-you-type TextBox and clear RadButton elements

   C#

   	public partial class MainWindow : Window
   	{
   	    private TextBox searchTextBox;
   
   	    public MainWindow()
   	    {
   	        InitializeComponent();
   
   			this.radGridView.Loaded += OnRadGridViewLoaded;
   	    }
   
   	    private void OnRadGridViewLoaded(object sender, RoutedEventArgs e)
   	    {
   	        RadGridView radGridView = (RadGridView)sender;
   
   	        TextBox searchAsYouTypeTextBox = radGridView.ChildrenOfType<TextBox>().FirstOrDefault(x => x.Name == "PART_SearchAsYouTypeTextBox");
   	        RadButton clearButton = radGridView.ChildrenOfType<RadButton>().FirstOrDefault(x => x.Name == "ClearButton");
   
   	        if (searchAsYouTypeTextBox != null && clearButton != null)
   	        {
   	            this.searchTextBox = searchAsYouTypeTextBox;
   	        }
   	    }
   	}

   VB.NET

   	Public Partial Class MainWindow
   	    Inherits Window
   	    Private searchTextBox As TextBox
   
   	    Public Sub New()
   	        InitializeComponent()
   
   	        Me.radGridView.Loaded += AddressOf OnRadGridViewLoaded
   	    End Sub
   
   	    Private Sub OnRadGridViewLoaded(ByVal sender As Object, ByVal e As RoutedEventArgs)
   	        Dim radGridView As RadGridView = CType(sender, RadGridView)
   
   	        Dim searchAsYouTypeTextBox As TextBox = radGridView.ChildrenOfType(Of TextBox)().FirstOrDefault(Function(x) x.Name Is "PART_SearchAsYouTypeTextBox")
   	        Dim clearButton As RadButton = radGridView.ChildrenOfType(Of RadButton)().FirstOrDefault(Function(x) x.Name Is "ClearButton")
   
   	        If searchAsYouTypeTextBox IsNot Nothing AndAlso clearButton IsNot Nothing Then
   	            searchTextBox = searchAsYouTypeTextBox
   	        End If
   	    End Sub
   	End Class

2. Set the Command property of the RadButton element to null and subscribe to its Click event. In the added event handler, clear the Text property of the cached TextBox, as well as the SearchText property of its DataContext. Its DataContext will be of the type SearchViewModel.

   Subscribe to the Click event of the clear RadButton

   C#

   	clearButton.Command = null;
       clearButton.Click += ClearButton_Click;
   
   	private void ClearButton_Click(object sender, RoutedEventArgs e)
   	{
       	this.searchTextBox.Text = "";
       	((SearchViewModel)this.searchTextBox.DataContext).SearchText = "";
   	}

   VB.NET

   	clearButton.Command = Nothing
       clearButton.Click += AddressOf ClearButton_Click
   
   	Private Sub ClearButton_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)
       	searchTextBox.Text = ""
       	CType(searchTextBox.DataContext, SearchViewModel).SearchText = ""
   	End Sub

3. Subscribe to the LostKeyboardFocus event of the search-as-you-type TextBox. In the added event handler, if clear RadButton is the new element that receives the focus, raise its Click event.

   Subscribe to the LostKeyboardFocus event of the search-as-you-type TextBox

   C#

   	this.searchTextBox.LostKeyboardFocus += SearchTextBox_LostKeyboardFocus;
   
   	private void SearchTextBox_LostKeyboardFocus(object sender, KeyboardFocusChangedEventArgs e)
   	{
   	    if (e.NewFocus is RadButton radbutton)
   	    {
   	        if (radbutton.Name == "ClearButton")
   	        {
   	            radbutton.RaiseEvent(new RoutedEventArgs(RadButton.ClickEvent));
   	        }
   	    }
   	}

   VB.NET

   	Me.searchTextBox.LostKeyboardFocus += AddressOf SearchTextBox_LostKeyboardFocus
   
   	Private Sub SearchTextBox_LostKeyboardFocus(ByVal sender As Object, ByVal e As KeyboardFocusChangedEventArgs)
       Dim radbutton As RadButton = Nothing
   
       	If CSharpImpl.__Assign(radbutton, TryCast(e.NewFocus, RadButton)) IsNot Nothing Then
       	    If radbutton.Name Is "ClearButton" Then
       	        radbutton.[RaiseEvent](New RoutedEventArgs(RadButton.ClickEvent))
       	    End If
       	End If
   	End Sub
   
   	Private Class CSharpImpl
       	Shared Function __Assign(Of T)(ByRef target As T, value As T) As T
       	    target = value
       	    Return value
       	End Function
   	End Class

The full implementation of this solution is as follows:

C#

	public partial class MainWindow : Window
	{
	    private TextBox searchTextBox;
	
	    public MainWindow()
	    {
	        InitializeComponent();
	    }

	    private void RadGridView_Loaded(object sender, RoutedEventArgs e)
	    {
	        RadGridView radGridView = (RadGridView)sender;

	        TextBox searchAsYouTypeTextBox = radGridView.ChildrenOfType<TextBox>().FirstOrDefault(x => x.Name == "PART_SearchAsYouTypeTextBox");
	        RadButton clearButton = radGridView.ChildrenOfType<RadButton>().FirstOrDefault(x => x.Name == "ClearButton");

	        if (searchAsYouTypeTextBox != null && clearButton != null)
	        {
	            this.searchTextBox = searchAsYouTypeTextBox;
	            this.searchTextBox.LostKeyboardFocus += SearchTextBox_LostKeyboardFocus;

	            clearButton.Command = null;
	            clearButton.Click += ClearButton_Click;
	        }
	    }

	    private void SearchTextBox_LostKeyboardFocus(object sender, KeyboardFocusChangedEventArgs e)
	    {
	        if (e.NewFocus is RadButton radbutton)
	        {
	            if (radbutton.Name == "ClearButton")
	            {
	                radbutton.RaiseEvent(new RoutedEventArgs(RadButton.ClickEvent));
	            }
	        }
	    }

	    private void ClearButton_Click(object sender, RoutedEventArgs e)
	    {
	        this.searchTextBox.Text = "";
	        ((SearchViewModel)this.searchTextBox.DataContext).SearchText = "";
	    }
	}

VB.NET

	Public Partial Class MainWindow
	    Inherits Window

	    Private searchTextBox As TextBox

	    Public Sub New()
	        InitializeComponent()
	    End Sub

	    Private Sub RadGridView_Loaded(ByVal sender As Object, ByVal e As RoutedEventArgs)
	        Dim radGridView As RadGridView = CType(sender, RadGridView)
	        Dim searchAsYouTypeTextBox As TextBox = radGridView.ChildrenOfType(Of TextBox)().FirstOrDefault(Function(x) x.Name = "PART_SearchAsYouTypeTextBox")
	        Dim clearButton As RadButton = radGridView.ChildrenOfType(Of RadButton)().FirstOrDefault(Function(x) x.Name = "ClearButton")

	        If searchAsYouTypeTextBox IsNot Nothing AndAlso clearButton IsNot Nothing Then
	            Me.searchTextBox = searchAsYouTypeTextBox
	            Me.searchTextBox.LostKeyboardFocus += AddressOf SearchTextBox_LostKeyboardFocus
	            clearButton.Command = Nothing
	            clearButton.Click += AddressOf ClearButton_Click
	        End If
	    End Sub

	    Private Sub SearchTextBox_LostKeyboardFocus(ByVal sender As Object, ByVal e As KeyboardFocusChangedEventArgs)
	        Dim radbutton As RadButton = Nothing

	        If CSharpImpl.__Assign(radbutton, TryCast(e.NewFocus, RadButton)) IsNot Nothing Then

	            If radbutton.Name = "ClearButton" Then
	                radbutton.[RaiseEvent](New RoutedEventArgs(RadButton.ClickEvent))
	            End If
	        End If
	    End Sub

	    Private Sub ClearButton_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)
	        Me.searchTextBox.Text = ""
	        (CType(Me.searchTextBox.DataContext, SearchViewModel)).SearchText = ""
	    End Sub

	    Private Class CSharpImpl
	        Shared Function __Assign(Of T)(ByRef target As T, value As T) As T
	            target = value
	            Return value
	        End Function
	    End Class
	End Class